Just started cold crashing, didnt give any thought to beer temp at bottling time. Although i used i calc to figure out priming sugar based on style and temp of beer i never bottled beer at 40 ish degrees. Will my beet be ok?
Bottling beer after cold crash?
- Thread starter spunxter
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chickypad
lupulin shift victim
It's fine, just let it warm up after it's bottled. If you're using a calculator with temp use the highest ferm temp the beer achieved, not the current temp.
I agree it should be fine, but you may need to consider amount of headspace which may contain CO2, prior to cold-crashing. Some of that CO2 may dissolve back into the solution. But assuming headspace is small fraction of overall volume, it should be a small correction.
The complete analysis of CO2 reabsorption during cold crashing is in this post. The net is that reabsorption is a non-issue. As @chickypad said, use the highest temp the beer has been after the end of fermentation in the priming sugar calculator.
Brew on
chickypad
lupulin shift victim
ugh - @doug293cz you just forced me to re-read that post and try to understand the math again, dammit! 
I'll stick to remembering the bottom line - use the highest temp
I'll stick to remembering the bottom line - use the highest temp
Sorry to darken your Sunday.ugh - @doug293cz you just forced me to re-read that post and try to understand the math again, dammit!
I'll stick to remembering the bottom line - use the highest temp
Brew on
The complete analysis of CO2 reabsorption during cold crashing is in this post. The net is that reabsorption is a non-issue. As @chickypad said, use the highest temp the beer has been after the end of fermentation in the priming sugar calculator.
Brew on
excellent analysis, doug - as usual!
I agree that one DEFINITELY should not use cold-crashing temperature in a calculator. I went through the numbers, very impressive. It's actually even slightly worse, because the volume of the liquid will shrink, by about 0.5%-0.7% from 70F to 30F, leaving more headspace in cold condition, so slightly less CO2 will be adsorbed (especially for small headspace percentage - it could expand considerably then).
One can do a somewhat more basic estimate - assume CO2 is at 1 volume (which is true at ~61F, but let's just go with it), and assume about half headspace CO2 gets into the liquid (it's not exactly 0.5, but for most scenarios around that number). So if you have 10% of headspace (say 0.5G headspace and 4.5G liquid) and CO2 basically uniformly distributed, you may adsorb about 5% into the beer. So instead of carbonation of 1 volume, you will be at 1.05 volumes. And so if you are carbing to 2.5 volumes, which means you adding sugar proportional to 2.5-1=1.5, it's actually slightly off and you need only 1.45 or so (2.5-1.05=1.45). So even smaller error than 5%.
But one has to be more careful when headspace is huge. I doubt it's a real issue for most (any?) of us, but if lets say someone crazy has 50% headspace (say 3G liquid 3G headspace/CO2), and it's a lightly carbonated beer - let's say calling for only 2 volumes, then uncertainty get larger. Instead of 1 volume from calculator, one would get 1.5 volumes since 50% of headspace CO2 will go into the beer - over long term, and then ideally one would have to cut the amount of sugar added in 2 (to add 0.5 volumes instead of a full 1.0 volume) to get carbonation right.
But this is such an extreme example, I agree, the correction is normally below 10% or so for most typical scenarios. Go with the highest fermentation temperature provided you stayed at that temperature for a few days to equilibrate.
petrolSpice
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For priming sugar calcs, use the highest temp the beer achieved post fermentation. I raise my beer to around 72 for a few days to help it clean up. This is the temp I use for priming sugar. Carbonation comes out great.
You are correct. With a larger headspace volume to beer volume ratio, there can be more CO2 absorption during cold crashing.
Since I have a handy-dandy spreadsheet set up to do this calculation, I decided to run your example. I used 12 L beer, 12 L headspace, 2.0 volumes carb target, final fermentation temp of 22˚C (71.6˚F), and cold crash temp of 0˚C. For this case, if cold crashing were long enough for the CO2 in the headspace to equilibrate with the beer, then the beer would absorb an additional 0.26 volumes from the headspace. Using the highest temp in the priming calculator would call for 1.21 volumes worth of sugar to be added, but using the coldest temp would call for 0.95 volumes worth of sugar. The worst case overcarb would be 13%.
Revisiting the original example: 20 L beer, 4 L headspace, 2.5 volumes carb target, final ferm temp 20˚C (68˚F), and cold crash temp of 1˚C (33.8˚F), and an improved state equation for CO2 in beer vs the one used in the original example, the maximum CO2 reabsorption is 0.068 volumes, for a worst case overcarb of 2.7%.
Brew on
